Many years ago we went on a cruise to the Caribbean islands. 25th wedding anniversary. We each bought a Breitling watch, as they were about half the price of what we would pay here.
On arrival back at Gatport Airwick I thought we are nice honest people so we went into the red corner. No one there, as it was 05:30 hrs. A notice said 'if the desk isn't attended please dial 0 on the telephone'. So that's what I did. The snoring from the other end subsided and he groaned "what do you want?"
"We brought a couple of Breitling watches in the caribbean"
"Are you wearing them?"
"Yes"
"Well, they are second hand then, we aren't interested. Go home"
Edit:
More recently on visits particularly to Norway we bought a few innocuous things like nice warm outdoor coats, and provided you buy them at the port shop they deduct the VAT at the point of sale.